Tonight or any autumn evening look for the constellation Cassiopeia the Queen lighting up the northeast sky. As night deepens Cassiopeia swings above Polaris, the North Star, and by dawn she is found in the northwest.
Cassiopeia has the distinctive shape of a W or an M depending on the time you see her and is circumpolar (visible all night throughout the year). She was first catalogued by the Greek astronomer Ptolemy in the 2nd century AD and comprises some of our brightest stars, including Schedar, Caph, Gamma Cassiopeiae, Ruchbah, and Segin. A rich section of the Milky Way runs through Cassiopeia containing several notable deep-sky objects, including the Heart Nebula, the Soul Nebula, the Pacman Nebula and the White Rose Cluster.
According to Greek mythology Cassiopeia was an Ethiopian queen who claimed to be more beautiful than the sea-nymphs known as Nereids. Cassiopeia's boast angered Poseidon who sent the sea monster Cetus to ravage her kingdom. To pacify Cetus Cassiopeia's daughter, Andromeda, was tied to a rock by the sea for him to devour. Fortunately, Perseus arrived on his flying horse, Pegasus, and scooped Andromeda up first to safety and then to wedlock. The gods showed their pleasure by elevating all the characters to the heavens.
However, Cassiopeia's vanity had to be paid for. She was forced to wheel around the North Celestial Pole spending half her time clinging to her throne so she does not drop into the ocean below, where the Nereids are still waiting. Whilst at nightfall we see Cassiopeia in the shape of an M, reclining on her starry throne, in the early hours of the morning and during late winter her chair dips below the celestial pole and appears more like the letter W. It is then that the Lady of the Chair, as Cassiopeia is sometimes called, is said to hang on for dear life.
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Copyright © Karen Meadows 2018